KR20180044703A - Au―Pd supra nanoparticle, method for preparing the same, and sensor including the same for detecting hydrogen peroxide - Google Patents

Abstract

According to an embodiment of the present invention, a method for preparing a gold-palladium supra nanoparticle comprises: a first step of preparing a seed solution including a gold (Au) nanoparticle; a second step of preparing a first mixed solution by adding cetyltrimethylammonium bromide (CTAB) and 5-bromosalicylic acid (5-BrSA) solutions to the seed solution; a third step of preparing a second mixed solution by adding a solution including a palladium (Pd) precursor to the first mixed solution; and a fourth step of adding ascorbic acid to the second mixed solution. Accordingly, a gold-palladium supra nanoparticle having a high surface area can be provided, and a sensor having high sensing capability for hydrogen peroxide can be provided.

Description

[0001] The present invention relates to a gold-palladium supra nano particle, a method for producing the same, and a sensor for detecting hydrogen peroxide including the same,

The present invention relates to gold-palladium bimetallic supra nanoparticles having a large surface area.

Bimetallic nanostructures exhibit new properties due to the synergistic effects of the two metals through bonding. For example, gold-palladium bimetallic nanoparticles exhibit higher reaction kinetics than individual gold or palladium nanoparticles. It also serves as an excellent catalyst for the electro-oxidation of molecules and other chemical reactions. In addition, the catalytic properties of palladium nanostructures are coupled with the optical properties of gold nanoparticles. The synergistic effect of such bimetallic nanostructures can be improved by controlling the components of gold and palladium, or by controlling the size or shape of the gold-palladium shell nanostructures.

In addition to the development of such bimetallic nanostructures, studies have been continued to expand the surface area of nanostructures in order to improve the performance of the nanoparticles. The formation of bimetallic nanostructures of superstructure or formation of supra-nanoparticles increases surface area. These nanoparticles refer to single metal center nanoparticles often surrounded by discrete nanostructures of different metals, which are quite different from core-shell bi-metallic structures in that there is no continuous shell. The core nanoparticles may serve as a support for stabilizing the surrounding nanoparticles, or may be sites where crystals can grow from their surfaces. Some bimetallic supra nano-particles are known to catalyze chemical reactions similar to core-shell nanoparticles, but suprapanoparticles are most likely to respond due to their high volume-to-surface surface area caused by the surrounding nanoparticles Is superior to a single metal. And, while single metal supramolecular nanoparticles are produced in a single pot, bimetallic supramolecular nanoparticles introduce seed nanoparticles of a certain shape and lattice structure.

Platinum (Pt) nanodendrite could be obtained from the growth of platinum on the surface of seed nanoparticles. Platinum nanoparticles were also deposited on gold nanorods to obtain rectangular bimetallic nanostructures. For gold-palladium supragranules, the gold-palladium nanostructures could be prepared by selectively removing silver from gold-silver / palladium nanoparticles. A bimetallic nanostructure in the form of a gold core-palladium flower is prepared by dispersing small palladium nanoparticles on spherical gold nanoparticles in the presence of poly- (vinylpyrrolidone), PVP and hydroquinone . Recently, a single-process synthesis method of gold-palladium core-shell nanofluorescence supported on graphene oxide in the presence of melanin and PVP has been reported, and a gold- A synthesis method of palladium nano dendrite has been reported.

However, it is necessary to study the factors that can play an important role in determining the morphology of bimetallic nanoparticles. Regardless of the type of nanoparticles, it is important to control the surface of the bimetallic nanostructure. As such techniques, stabilizers such as CTAB and CTAC have been introduced to control the surface structure of palladium in gold nano-rods, but there is still a general and versatile method for synthesizing supra-nanoparticles of various core nanoparticles It is time to research on technology.

It is an object of the present invention to provide a method for producing gold-palladium supra nanoparticles having excellent catalyst and sensing ability and having a large surface area.

A method for preparing gold-palladium supramolecular nanoparticles, which is an embodiment of the present invention, includes the steps of preparing a seed solution containing gold (Au) nanoparticles, adding cetyltrimethylammonium bromide (CTAB) to the seed solution, bromide and 5-bromosalicyclic acid to prepare a first mixed solution; adding a solution containing palladium (Pd) precursor to the first mixed solution; A third step of preparing a second mixed solution, and a fourth step of adding ascorbic acid to the second mixed solution.

In another embodiment, the gold nanoparticles in the first step are one of a rod, a sphere, and a cube.

In another embodiment, the second step comprises the steps of: a) first centrifuging the seed solution, b) adding CTAB and 5-BrSA solution, c) second centrifuging, d) redispersion in deionized water do.

In another embodiment, the palladium precursor in the third step is H ₂ PdCl ₄ .

In another embodiment, the third step further comprises ultrasonicating the second mixed solution.

In another embodiment, the fourth step further comprises the step of adding ascorbic acid followed by inversion.

Another embodiment of the present invention is a gold-palladium supramolecular nanoparticle produced by the above-described embodiment, wherein the gold-palladium supramolecular nanoparticle comprises gold nanoparticles and palladium nanoparticles grown perpendicularly to the surfaces of the gold nanoparticles .

In another embodiment, the palladium nanoparticles are anisotropic.

In another embodiment, the length of the palladium nanoparticles is 17-25 nm.

Another embodiment of the present invention is a sensor for detecting H ₂ O ₂ comprising gold-palladium supramolecular nanoparticles manufactured through the above-described embodiments, wherein the gold-palladium supramolecular nanoparticles are composed of gold nanoparticles and gold nanoparticles And palladium nanoparticles grown perpendicular to the surface of the substrate.

In another embodiment, the palladium nanoparticles are anisotropic.

In another embodiment, the length of the palladium nanoparticles is 17-25 nm.

According to one embodiment of the present invention, it is possible to provide gold-palladium suprastar nanoparticles having a high surface area, and thereby, a high sensing ability for hydrogen peroxide can be exhibited. In addition, the structure of gold nanoparticles can be applied to both rod, sphere, and cube shapes.

FIG. 1 is a schematic view of a method for manufacturing gold-palladium supra nanoparticles according to an embodiment of the present invention.
2 (a) is a SEM photograph of the gold-nano-rods used in the synthesis.
FIG. 2 (b) is a SEM photograph of synthesized gold-palladium sufran nanoparticles.
FIG. 3 is a SEM photograph of synthesized gold-palladium sufran nanoparticles. FIG.
FIG. 4 is a TEM photograph of synthesized gold-palladium sufran nanoparticles.
5 (a) is a TEM photograph of the synthesized gold-palladium supramolecular nanoparticles.
Figures 5 (b), (c) and (d) are Pd, Au, and elemental maps of Pd and Au.
6 (a) to (d) are TEM photographs of gold-palladium sufran particles according to H ₂ PdCl ₄ concentration.
7 is a SEM photograph of gold-nanorod Palladium core-shell nanoparticles.
8 (a) is a TEM photograph of a gold nanosphere.
FIG. 8 (b) is a SEM photograph of gold-palladium supraphenol nanoparticles synthesized using gold nanoparticles.
9 (a) is a TEM photograph of a gold nanocube.
FIG. 9 (b) is a SEM photograph of gold-palladium supramolecular nanoparticles synthesized using gold nanocubes.
Figure 10 is a graph showing the CV of GCE treated with gold-palladium suprapranoparticles (i) and gold-palladium continuous shell (ii).
Figure 11 is a graph showing the CV of GCE treated with gold-palladium supraphonanol (i) and gold-palladium continuous shell (ii).
12 (a) is a graph showing the CV of GCE according to the concentration of hydrogen peroxide.
12 (b) is a calibration curve (R ² = 0.99) graph for hydrogen peroxide detection with hydrogen peroxide concentration.
FIG. 12 (c) is a graph showing the sensitivity of GCE to hydrogen peroxide detection.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the term " comprises " or " having " is intended to designate the presence of stated features, elements, etc., and not one or more other features, It does not mean that there is none.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the contextual meaning of the related art and are to be interpreted as either ideal or overly formal in the sense of the present application Do not.

A method for preparing gold-palladium supramolecular nanoparticles, which is an embodiment of the present invention, includes the steps of preparing a seed solution containing gold (Au) nanoparticles, adding cetyltrimethylammonium bromide (CTAB) to the seed solution, bromide and 5-bromosalicyclic acid to prepare a first mixed solution; adding a solution containing palladium (Pd) precursor to the first mixed solution; A third step of preparing a second mixed solution, and a fourth step of adding ascorbic acid to the second mixed solution. The manufacturing method described above in Fig. 1 is schematically shown. As shown in Fig. 1, the surface of gold nanoparticles (rods, spheres, cubes) serving as cores is densely packed with palladium nanoparticles to anisotropically grow to provide gold-palladium bimetallic supramolecular nanoparticles have.

Seed ( seed ) Solution preparation

In one embodiment of the present invention, first, a seed solution containing gold (Au) nanoparticles is prepared. The gold nanoparticles may be in the form of a rod, a sphere, or a cube.

The gold nanorods are capped by CTAB. First, to prepare the seed solution, the CTAB solution and the gold precursor solution are mixed. The gold precursor HAuCl may be _four days. Add the reducing agent and stir. At this time, the reducing agent is NaBH ₄ may work. The resulting mixed solution exhibits a brown-yellow color. Then, the mixed solution is allowed to stand at room temperature for a certain period of time. In a preferred embodiment, 10 mL of 0.2 M CTAB and 5 * 10 ^-4 M HAuCl ₄ , 1.2 mL of cold 0.01 M NaBH _{4 was} added, stirred for 2 minutes, and then allowed to stand at room temperature for about 10 minutes.

In addition, HAuCl ₄ , AgNO ₃ , and CTAB are prepared to prepare a growth solution. To the prepared mixed solution, ascorbic acid is added and an HCl solution is added. As a preferred example, HAuCl ₄ (0.01 M, 4 mL), AgNO ₃ (0.01 M, 0.8 mL) and CTAB (0.1 M, 80 mL) were mixed and ascorbic acid (0.1 M, 0.64 mL) Add aqueous solution (1.0 M, 1.6 mL) and invert.

Then, the seed solution is added to the growth solution to prepare a gold seed solution. It is preferable to invert for about 10 seconds and leave it for 6 hours or more.

In the case of gold nanoparticles, HAuCl ₄ The solution is stirred in an oil bath while heating. After adding the sodium citrate solution, wait until the color of the solution becomes ruby red, and then obtain a gold nanocrystal seed solution. As a preferred embodiment, it is preferable to stir HAuCl ₄ (2.5 * 10 ^-4 ) solution for 30 minutes while heating to 120 ° C, wait for 20 minutes after adding sodium citrate (1%, 10 mL) solution.

In the case of gold nanocubes, NaBH ₄ is added to a solution of CTAB solution and HAuCl ₄ for seeding, then rapidly inversion and stored at room temperature. As a preferred embodiment, NaBH ₄ (0.01 M, 0.6 mL) was added to a solution of a solution of CTAB (0.1 M, 7.5 mL) and HAuCl ₄ (0.01 M, 0.25 mL) For one hour. And, for the growth solution, HAuCl ₄ , CTAB and ascorbic acid are added to water. In a preferred embodiment, the _{HAuCl 4 (0.01M, 0.8mL),} CTAB (0.1M, 6.4mL) and ascorbic acid (0.1M, 3.8mL) is preferably added to water (32mL). Then, the seed solution is added to the growth solution, and then the seed solution is inverted and stored.

CTAB  And 5- Brsa  Addition (gold nanoparticle coating)

Then, a solution of cetyltrimethylammonium bromide (CTAB) and 5-bromosalicyclic acid (5-BrSA, 5-bromosalicyclic acid) is added to the prepared seed solution to prepare a first mixed solution. The CTAB and 5-BrSA may be added to protect the surface of gold nanoparticles.

Specifically, the seed solution is preferably centrifuged and then added to and dispersed in the CTAB and 5-BrSA solution. It is preferable to centrifuge the first mixed solution again and redisperse in deionized water. As a specific example, 10 mL of the seed solution was centrifuged at 8000 rpm for 10 minutes, then 10 mL of CTAB and 5-BrSA (0.05 M CTAB and 0.0126 M 5-BrSA) solution was added, followed by a second centrifugation, It is preferable to redisperse in several 10 mL of water.

CTAB is known to play a significant role in the selective growth of palladium because it prefers bonding to the {100} facet of gold nano-rods. The addition of aromatic acid to CTAB can produce a double layer CTAB that maintains a regular separation distance from the acid. Binding of the CTAB double layer to the acid reduces the electrostatic repulsion between the CTAB molecules and changes the spherical micelle structure into a threaded or rod-shaped micelle. At this time, the mixing ratio is preferably an acid: CTAB = 1: 1 to 10. Since the present invention provides gold-palladium nanoparticles having a maximum surface area of palladium bonded to gold nanoparticles in order to maximize the function of palladium, the role of the surface treatment agent described above is still important.

Specifically, 5-BrSA plays an important role in binding palladium to the surface of gold nanoparticles. As noted above, 5-BrSA is located at a constant distance between the CTAB layers, which is due to the carboxylic acid functionality towards CTAB. Thus, PdCl ₄ ^{2 -} ions drawn by the CTAB bilayer are not accessible near the site where 5-BrSA is located because of the carboxylic acid functionality of 5-BrSA and the repulsion of PdCl ₄ ^{2 -} ions. For this reason, palladium does not allow continuous growth to form a shell. Thus, if 5-BrSA is not added, gold-palladium core-shell nanoparticles are formed.

Pd  Solution addition

Then, a solution containing a palladium (Pd) precursor is added to the first mixed solution to prepare a second mixed solution. The palladium precursor is preferably H ₂ PdCl ₄ .

Specifically, the first mixed solution may be added to the solution containing the palladium precursor to prepare the second mixed solution, and then the ultrasonic treatment may be performed. As a specific example, 10 mL of the first mixed solution is added to 0.001 MH ₂ PdCl ₄ and ultrasonicated for 1 minute.

Ascorbic acid  process

Then, ascorbic acid is added to the second mixed solution. Concretely, it is preferable to add ascorbic acid to the second mixed solution, rapidly invert the solution, and then leave the solution. As a specific example, 1 mL of 0.01 M ascorbic acid is added, and the mixture is inverted for 10 seconds and then left to stand for at least 6 hours.

Through the treatment with ascorbic acid, the palladium ions are reduced. In addition, through inversion, the objects can be mixed for the purpose intended by the present invention.

In another embodiment of the present invention, there is provided a gold-palladium supramolecular nanoparticle produced by the above-described embodiment, wherein the gold-palladium supramolecular nanoparticle comprises gold nanoparticles and palladium Nanoparticles. The palladium nanoparticles are anisotropic. Here, the length of the palladium nanoparticles is 17 to 25 nm. Bimetallic supra nano-particles thus prepared have a very large active surface area. The gold-palladium supra nano particles provide a higher active surface area in the catalytic role, as compared to core-shell nanoparticles, through which they can exhibit high electrochemical properties. It also exhibits high hydrogen peroxide detection capability.

In addition, another embodiment of the present invention is a sensor for detecting H ₂ O ₂ comprising gold-palladium supramolecular nanoparticles manufactured through the above-described embodiments, wherein the gold-palladium supramolecular nanoparticles are composed of gold nanoparticles and gold And palladium nanoparticles grown perpendicular to the surface of the nanoparticles. The palladium nanoparticles are anisotropic. The length of the palladium nanoparticles is 17 to 25 nm.

In order to use the above-described gold-palladium supramolecular nanoparticles as an electrocatalyst, it is preferable to remove the residual surface treatment agent (CTAB / 5-BrSA) existing on the surface of the gold-palladium nanoparticles. It is preferable that the nanoparticles are washed and re-dispersed in deionized water. Then, it is dropped-cast onto a glassy carbon electrode (GCE). The electrode thus treated can be washed again with water and used as an electrode.

The electrode treated with the supraprano particle quickly responds to the addition of analytes. This rapid reaction is due to the rapid uptake of H ₂ O ₂ on the surface of the supra nano-particles and electrocatalysis.

Hereinafter, the present invention will be described in detail with reference to specific examples.

Materials required for the experiment were purchased from Sigma-Aldrich. Gold nanorods were synthesized in a CTAB aqueous solution through a seed - mediated growth method. The synthesized gold nanorods were used as a template for the synthesis of the suprapranoparticles. In the CTAB / 5-BrSA surface treatment mixture, CTAB was exchanged with a solution containing 0.05M CTAB and 0.0126M 5-BrSA in the synthesized gold nanorod solution using centrifugation in order to perform surface treatment of the gold nanorods . The ratio of 5-BrSA and CTAB was about 1: 4, which is known to provide a threaded anisotropic micellar structure. To remove excess CTAB / 5-BrSA, it was washed in deionized water through centrifugation and a 1 mM H ₂ PdCl ₄ solution was added (1: 5 volume / volume ratio). To disperse the nanoparticles, this mixture was sonicated. Then, 10 mM ascorbic acid was added. Fast for 10 seconds, and left uninterrupted for more than 6 hours.

The surface of gold nano-rods and suprapall gold-palladium nanoparticles was measured using FE-SEM (field-emission scanning electron microscopy). At this time, the measurement conditions were JSM-6700F, an acceleration voltage of 5 kV, and a working distance of 7-8 mm. The gold nanorods and gold-palladium sufran particles synthesized in FIGS. 2 (a) and 2 (b) are shown. As shown in Fig. 2 (a), the gold nanorods had a length of 59 6 nm and a thickness of 18 2 nm. On the other hand, as shown in FIG. 2 (b), it was confirmed that the average length (lengthwise direction) of the gold-palladium supramolecular nanoparticles was 110 ± 6 nm and the thickness was 64 ± 5 nm.

In order to confirm that supra nano particles can be uniformly synthesized in large amounts, an SEM image of gold-palladium supramolecular nanoparticles is shown in Fig.

In addition, the surface of supra nano-particles was measured using transmission electron microscopy (TEM). At this time, JEM-2010 intrument was used. The measured images are shown in Fig. As shown in FIG. 4, it was confirmed that a clear anisotropic palladium nanostructure was tightly bound to the surface of gold nano-rods.

Through FIGS. 2 and 4, the length of the palladium nanostructure was 17 to 25 nm. This is the value obtained using SEM (25 ± 2) and TEM (17 ± 2).

In addition, in order to confirm that the gold nano-rods are surrounded by palladium nanostructures, component mapping is performed using energy-dispersive X-ray spectroscopy, d). 5 (a) is a TEM photograph of gold-palladium supramolecular nanoparticles, (b) is palladium, (c) is gold, and (d) is palladium and gold. As shown in Figs. 5 (a) to 5 (d), it was confirmed that palladium surrounded the gold nanorods.

Additional experiments were conducted to determine how palladium nanoparticles grew from the gold nanorodsides. The concentration of CTAB / 5-BrSA was fixed, but the concentration of H ₂ PdCl ₄ was changed from 10 ^-5 to 10 ^-3 M. The other experimental conditions were the same as in Example 1. The TEM image and SEM image of the gold-palladium nanoparticles thus obtained are shown in FIG. 6. (A) TEM image of H ₂ PdCl ₄ concentration of 10 ^-5 (5 mL), (b) H ₂ PdCl ₄ concentration of 10 ^-4 (C) H ₂ PdCl ₄ concentration 10 ^-3 (5 mL) TEM image (d) H ₂ PdCl ₄ concentration 10 ^-3 (5 mL) TEM image (left) and SEM Image (right).

As shown in FIG. 6 (a), when the concentration of H ₂ PdCl ₄ is 10 ^-5 (5 mL), a rounded, elongated island-shaped palladium nanostructure is formed on the gold nanorod I could confirm. The elongated island-shaped lattice fringes were parallel to the [001] direction of the gold nanorods. According to the SAD ((selected area diffraction) patterns, the {100} plane of palladium nano structure was confirmed that the nearly exposed on the surface, and, in Fig. 6 (b) and, H ₂ PdCl _4, as shown in (c) If the (5mL) concentration of ^10-4, were able to resolve the various morphologies formed with one portion (FIG. 6 (b)) in, the palladium was nanostructures are grown in a vertical direction, grown along the length of the gold nanorod In the other part (Fig. 6 (c)), the vertically grown anisotropic palladium nanostructures were grown from the surface of the gold nanorods. SAD analysis revealed that the surface of the nanostructures was almost exposed to the {100} and {111} surfaces, but the shape and size of the palladium nanostructures were unified at the intermediate stage of growth. (d), it was confirmed that when fully grown, the palladium nanostructures were randomly arranged, and secondary growth was observed on already existing palladium nanostructures, especially vertically aligned palladium nanostructures It seemed to have occurred.

In order to confirm 5-BrSA addition, 5-BrSA was not added and the concentration of H ₂ PdCl ₄ was 10 ^-3 (5 mL). The other experimental conditions were the same as those of Example 2 Respectively. An SEM image of the obtained gold-palladium nanoparticles is shown in Fig. As shown in Fig. 7, it was confirmed that the rectangular gold-palladium nanoparticles formed a continuous palladium shell.

Additional experiments were conducted to determine whether CTAB / 5-BrSA showed the same effect, even when the seeds were spherical or cubic. Gold nano spheres and nanocubes were used as seeds, and experiments were conducted under the same experimental conditions as in Example 1. [ FIG. 8 (a) shows a TEM image of gold nanoparticles, and FIG. 8 (b) shows an SEM image of gold-palladium sufran particles using gold nanoparticles (the scale bar in the upper right image is 20 nm). 9 (a) shows a TEM image of gold nanocubes, and FIG. 9 (b) shows an SEM image of gold-palladium sufran particles using gold nanocubes (the scale bar in the upper right image is 20 nm) .

As shown in Figs. 8 and 9, an anisotropic palladium nanostructure grown intensively on the surface of gold nanoparticles was confirmed. It was confirmed that CTAB / 5-BrSA is a surface treatment agent capable of producing gold-palladium suprapran particles having a high surface area irrespective of the geometry structure and crystal structure of gold nanoparticle seeds.

Additional experiments were conducted to confirm the electrocatalytic activity of gold-palladium supra nanoparticles. 10 shows the results of a circulation experiment using a glassy carbon electrode modified with gold-palladium sub-nanoparticles in a 0.1 M saturated H ₂ SO ₄ solution in nitrogen gas at -0.2-1.6 V, A graph (i) of the result of CV (cyclic voltammetry) is shown and is shown by the graph (ii) of the result of CV using the gold-palladium core-continuous shell nanoparticles obtained in Example 3.

The electrochemically active surface area of the electrode can be measured through the CV curve of the hydrogen adsorption-desorption region. As shown in Fig. 10, the active surface area of the gold-palladium bismuth subcrystalline sub-nanoparticles was about 28.1 m ² / g, and the active surface area of the gold-palladium core-continuous shell was 7.3 m ² / g. It was confirmed that the gold-palladium supramolecular nanoparticle of the present invention exhibits an active surface area about four times higher than that of the gold-palladium core-continuous shell.

Additional experiments were conducted to confirm the electrochemical sensing ability of H ₂ O ₂ of gold-palladium supra nano-particles. Fig. 11 shows a graph (i) of a CV using a glassy carbon electrode treated with gold-palladium supramolecular nanoparticles in 0.1M PBS (pH 7.4) containing 5 mM H ₂ O ₂ at a scan rate of 50 mV ^-1 . (Ii) of the result of CV using the gold-palladium core-continuous shell nanoparticles obtained in Example 3.

As shown in Fig. 11, the curve i shows a relationship between H ₂ O ₂ A reduction peak appeared. On the other hand, Curve ii showed a less developed oxidation wave around -0.50 V, which showed a significant negative potential as compared to curve i. Through this, the low-reduction potential of gold-palladium suprapranoparticles with a wide electrochemically active surface area can be determined by H ₂ O ₂ It was confirmed to be very active in reduction.

In order to confirm the electrochemical sensing ability of H ₂ O ₂ of gold-palladium supra nano-particles, another experiment was conducted. The experiment was carried out while changing the concentration of H ₂ O ₂ from 1 μM to 10 mM, and the other experimental conditions were the same as in Example 6. The derived CV graph is shown in Fig. 12 (a). As shown in Fig. 12 (a), electrical reduction of H ₂ O ₂ concentration at all was started at about 0.15V, the more the concentration of H ₂ O ₂ increased, and increases the negative peak current (cathodic peak current). In addition, as the concentration of H ₂ O ₂ increases, the reduction peak potential of H ₂ O ₂ migrates to the more negative potential, which is increasingly the reaction between the glassy carbon electrode / gold-palladium supramolecular nanoparticles and H ₂ O ₂ Because it is a limitation.

The reduction peak current in the H ₂ O ₂ to the concentration of H ₂ O ₂ are shown in 12 (b). As shown in Fig. 12 (b), it was confirmed that the H ₂ O ₂ sensor had a detection limit at 1 μM and a large linear range from 1 μM to 1 mM. From the slope of the graph, the sensitivity was measured at 17.4 μA / mM. The figure of merit of gold-palladium supra nano-particles is better than that obtained from other single-metal (gold, silver, or palladium) nanoparticles.

In order to measure the sensitivity of the glassy carbon electrode treated with supra nano particles in order to detect H ₂ O ₂ , the current with respect to time at a fixed potential of -0.05 V was measured and shown in FIG. 12 (c). The inserted inset showed a time-to-time current for H ₂ O ₂ concentrations of 1 to 6 μM.

As shown in Fig. 12 (c), it is confirmed that the addition of H ₂ O ₂ to the saline buffer solution shows a typical amperometric response from the glassy carbon electrode treated with supraprano-particles I could. The electrode quickly responded to the addition of the analyte and was directed to a steady-state current within 3.3 ± 0.3 s. The sensitivity of the glassy carbon electrode treated with supra nano particles was 27 μA / mM and the detection limit was 1 μM. This rapid reaction is due to the rapid adsorption of H ₂ O ₂ on the surface of the supra nanoparticles and the electrocatalytic action.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the present invention as defined by the following claims. It can be understood that it is possible.

Claims (12)

A first step of preparing a seed solution containing gold (Au) nanoparticles;
A second step of adding a solution of cetyltrimethylammonium bromide (CTAB) and 5-bromosalicyclic acid (5-BrSA, 5-bromosalicyclic acid) to the seed solution to prepare a first mixed solution;
A third step of preparing a second mixed solution by adding a solution containing palladium (Pd) precursor to the first mixed solution; And
And a fourth step of adding ascorbic acid to the second mixed solution.
Method for manufacturing gold - palladium supra nano particles. The method according to claim 1,
The gold nanoparticles of the first step may be in the form of a rod, a sphere, or a cube,
Method for manufacturing gold - palladium supra nano particles. The method according to claim 1,
The second step comprises the steps of: a) first centrifuging the seed solution, b) adding CTAB and 5-BrSA solution, c) second centrifuging, and d) redispersing in deionized water.
Method for manufacturing gold - palladium supra nano particles. The method according to claim 1,
Wherein the palladium precursor in the third step is H ₂ PdCl ₄ ,
Method for manufacturing gold - palladium supra nano particles. The method according to claim 1,
Wherein the third step further comprises ultrasonicating the second mixed solution,
Method for manufacturing gold - palladium supra nano particles. The method according to claim 1,
Wherein the fourth step further comprises the step of adding ascorbic acid followed by inversion,
Method for manufacturing gold - palladium supra nano particles. 7. A gold-palladium submicron particle produced by any one of claims 1 to 6,
Wherein the gold-palladium supramolecular nanoparticles comprise gold nanoparticles and palladium nanoparticles grown perpendicular to the surface of the gold nanoparticles.
Gold - palladium supra nano particles. 8. The method of claim 7,
The palladium nanoparticles may be anisotropic,
Gold - palladium supra nano particles. 8. The method of claim 7,
Wherein the palladium nanoparticles have a length of 17 to 25 nm,
Gold - palladium supra nano particles. 7. A sensor for detecting H ₂ O ₂ comprising gold-palladium sufran particles produced by any one of claims 1 to 6,
Wherein the gold-palladium supramolecular nanoparticles comprise gold nanoparticles and palladium nanoparticles grown perpendicular to the surface of the gold nanoparticles.
H ₂ O ₂ Sensor for detection. 11. The method of claim 10,
The palladium nanoparticles may be anisotropic,
Sensor for H ₂ O ₂ detection. 11. The method of claim 10,
Wherein the palladium nanoparticles have a length of 17 to 25 nm,
Sensor for H ₂ O ₂ detection.

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